White-backed Woodpecker
Dendrocopos leucotus (Bechstein, 1802)
Photo © By Alastair Rae - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=9683842
STATUS
Eurasia. Polytypic.
OVERVIEW
Species not admitted nationally (BOU 1971).
NOT PROVEN
0). 1861 Shetland Halligarth, Unst, shot, 3rd September.
(J. Marshall, Zoologist 1861: 7753-54; H. L. Saxby, Zoologist, 1862: 7734; J. H. Gurney, jun., Zoologist 1875: 4695; S. H. Saxby Zoologist 1875: 4723).
[A. Newton, Zoologist 1881: 399-401; BOU, 1971].
History John Marshall of Taunton (1861) in The Zoologist, 1st series, Vol. XIX, p. 7753-54, dated 18th September, 1861, says: 'Spotted Woodpecker. September 3rd [1861]. I shot two in the garden at Halligarth, the wind having been blowing steadily from the S.E. since the 1st. One is a full-grown male, the other a young male of the year. This species sometimes occurs in Orkney, but has not hitherto been recorded as a visitor to Shetland."
J. H. Gurney, jun. (1875) in The Zoologist, 2nd series, Vol. X, p. 4695, says: 'In the Zoologist for 1861 (Zool. 7734) the late Dr. Saxby records a couple of Great Spotted Woodpeckers at Halligarth - the first ever killed in Shetland - and the forerunners of a movement which extended from Norfolk to the Faroe Islands. In 1865 a portion of that naturalist's collection passed into my possession, including one of the woodpeckers. My father at once judged it to be something more than a variety, and soon after, Messrs. Sharpe and Dresser being engaged in writing the history of this species for the Birds of Europe, I submitted my specimen to them: and, as they gave a lengthened description of it, I will only say that the chief points in which it differs from the young of P. major, L., are the very distinct streaks of brownish black down the sides of the breast and belly, the ash-grey wing-coverts and nape, and the pale vermilion vent. They were unable to say anything positive about the bird; but Mr. Gould asked for the loan of it, and made it out to be the young of the White-winged Woodpecker (Picus leuconotus), and before consulting his works on the Birds of Great Britain, he worthily installed it as a new British birds.'
Stephen H. Saxby of East Clevedon, Somerset (1875) in The Zoologist, 2nd series, Vol. X, p. 4723, says: 'In consequence of Mr. Gurney's interesting communication to the Zoologist for November respecting this bird, I have searched my brother's journals for the year in question [1861], and find reason to believe that almost all the birds in the flight which visited Shetland in the autumn of that year were of the species now determined by Mr. Gould to be P. leuconotus, and new to the British list. The first specimen obtained was certainly P. major, as shown by the minutely detailed cabinet description. All the others seen or shot appear to have markedly differed from it. My impression is that my brother was thrown off his guard by getting the P. major first, and assumed that the birds in company were of the same species in immature plumage. There is evidence of considerable perplexity, however, the abraded condition of beak and claws, so unusual in young birds, attracting repeated attention. It was explained by the supposition that the stones, amongst which the food had to be sought, in the almost entire absence of trees, had caused more than usual wear and tear....'
A. Newton (1881) in The Zoologist, 3rd series, Vol. V, pp. 399-401, dated 20th August, 1881, says: 'Since, of necessity, some time will elapse before the appearance of Part XV. of the revised edition of Yarrell's British Birds, to which I have to defer my remarks on the various foreign species of Picidae which are reported to have occurred in this country, it may interest the readers of the Zoologist to know that the claim advanced on behalf of one of them - Picus or (as I prefer calling it) Dendrocopus leuconotus, the White-backed Woodpecker - is, in my opinion, wholly inadmissible. That claim rests solely upon a specimen, said to be one of those which were recorded nearly twenty years ago (Zool. 7754, 7932) as obtained by the late Dr. Saxby in Shetland and referred to this species by the late Mr. Gould, by whom it was figured in his 'Birds of Great Britain,' as Mr. J. H. Gurney rightly states (Zool. s.s. 4695). Thanks to its owner, the gentleman last named, I have been allowed to examine it, and I may say that not much comparison was needed to excite my suspicion that Mr. Gould was absolutely mistaken in his determination of it. It was so minutely described by Messrs. Dresser and Sharpe, in their Birds of Europe, as a variety of Picus or (as I should say) Dendrocopus major, that I need not enter into many particulars.
Apart from size and the form of the beak, the most obvious distinction between D. major and D. leuconotus is that the latter has the middle of the back white, and the scapulars black, while in the former the allocation of these colours in those parts is reversed - D. major having conspicuous white scapulars (with a few occasional dark marks), and the back wholly black. In these respects Mr. Gurney's specimen entirely agrees with D. major - Mr. Gould's assertion, that "if the long black feathers of the back be lifted, a large amount of white will be found beneath," being contrary to fact. Again, in D. leuconotus that branch of the black mandibular stripe which passes upwards behind the ear-coverts does not meet the black of the head, while in D. major (except perhaps in examples from near Constantinople, which in this respect show a tendency towards D. syriacus) the same branch forms a complete post-auricular bar. Here again Mr. Gurney's bird agrees with D. major and not with D. leuconotus, though Mr. Gould's figure, taken from this very specimen, omits the bar altogether! Once more, D. leuconotus has large white spots on the greater wing-coverts, which are generally wholly wanting and never largely developed in D. major; and once more Mr. Gurney's bird agrees with D. major. Characters like these completely outweigh the slight resemblance that Mr. Gurney's bird bears to D. leuconotus in the indistinct streaks on the sides of the belly, which Mr. Gould thought were distinctive of the young of that species, for they occasionally occur in the young of D. major - though not, so far as my experience goes, in examples of British origin. But the history of Mr. Gurney's bird points to a foreign origin for it, since it was indubitably one of a number of refugees to the Shetlands (not "the Hebrides," by the way, as Mr. Gould inadvertently states), not very likely to have flown thither at that time of year (September) from any part of Great Britain. Finally to settle, as I hope, this point for ever, I have compared Mr. Gurney's bird with an unquestionably young specimen of D. leuconotus in the British Museum, obtained by Herr Meves at Onega, June 28th, 1869. This last resembles, as might be expected, the adult of the same species very closely, differing only just in the way that the young of most pied Woodpeckers differ from their seniors. Consequently it is wholly unlike Mr. Gurney's bird, which I can now affirm in the most positive manner is not D. leuconotus - and therefore the only claim for the admission of that species to the British list falls to the ground. Herein I may say that Mr. Seebohm, who kindly assisted me in my comparison of specimens at the British Museum, entirely concurs, as also does Mr. Salvin, though the latter had not the advantage of seeing so large a series of specimens.
Having thus proved, as I trust, that Mr. Gurney's bird is not a D. leuconotus (To obviate any future error on the subject, I may say that it differs just as strongly (though of course in other ways) from D. medius, which some, according to Saxby (Birds Shetl., p. 141), have supposed it to be.) the next thing of course was to find out what it is. Its most remarkable features, and those only which are peculiar to it, are the grey upper wing-coverts and hind-head (which, I may remark by the way, are characters separating it as widely from D. leuconotus as from any other species known to me). Next to these are the indistinct streaks in the sides of the belly and flanks, and the pale red of the vent. Mr. Seebohm has kindly shown me two specimens shot in Heligoland in October, 1876, out of a band of visitors similar, no doubt, to that which appeared in Shetland in the autumn of 1861. Both these are, like Mr. Gurney's, birds of the year, - a fact proved not only by their red heads, but by the first primaries, which among Woodpeckers seem to be always larger in the young than in adults, - and both of them exhibit (though one much more than the other) the indistinct iliac streaks and the pale red of the circum-anal region. But both of these birds have always been accounted specimens of D. major, the ordinary plumage of which they in other respects entirely match, and I think he would be a bold man who would venture to refer them to any other species (Indeed Naumann (Vog. Deutschl. V, p. 802) describes the young of this species as streaked with blackish on the thighs and flanks).
Accordingly it comes to pass that the only points in which Mr. Gurney's bird differs from examples of D. major are the before-mentioned grey upper wing-coverts and hind-head - for I should perhaps have mentioned before that in size it agrees absolutely with that species. Undoubtedly these parts ought to be black, but, when we know that albinescence, or canescence, is the effect of a physiological process from which there is reason to suppose that no birds are exempt, though it is much commoner in some groups than others, I think it is but right to ascribe the abnormal appearance of Mr. Gurney's bird to this cause; and hence I wholly subscribe to the opinion delivered more than ten years since by Messrs. Dresser and Sharpe, namely, that the bird shot at Halligarth, in Unst, on the 3rd of September, 1861, by the late Dr. Saxby, the skin of which is now in Mr. J. H. Gurney's collection, is a variety of the Greater Spotted Woodpecker, Dendrocopus major.'
Comment Not admitted nationally (BOU 1971). Not acceptable.
